Credit

Caption

Banded sea urchin (Echinothrix calamaris). The sea urchin is an echinoderm, a relative of the star fish. Its exoskeleton shell, or test, is covered in spines that protect it from predators. The banded sea urchin has two types of spine, long thin venomous spines capable of a nasty sting, and larger banded tubular spines with open ends. It is found near coral reefs in the Indo-Pacific region and can reach diameters of 15 centimetres. It feeds at night on algae that it scrapes from the surface of rocks. Photographed in the Red Sea.